Question

Anatomy Tutorial: Systemic Veins

Answer 1

\({\bf{Overview:}}\)
> unlike arteries veins are a bit more variable in terms of how many there are and where they are; some people are missing certain veins w/o much consequence to the circulation of blood
> in neck and limbs, there tend to be two sets of veins, one superficial and one deep to aid in thermoregulation via vasoconstriction and vasodilation

\({\bf{Superior~Vena~Cava:}}\) receives from head, neck, chest, shoulders, upper limbs
\({\bf{Brain~Drainage:}}\)
> superficial cerebral veins --> dural sinuses (sagittal sinuses, petrosal sinuses, occipital sinus, transverse sinuses, straight sinus) ---> left and right transverse sinuses --> sigmoid sinus --> internal jugular veins --> exits skull thru jugular foramen --> descends down neck along w/ common carotid artery
> vertebral veins: drain spinal cord and posterior skull --> braciocephalic vein

\({\bf{Head~and~Neck~Veins:}}\)
> converge, make temporal + facial + maxillary veins
- temporal + maxillary --> external jugular vein --> subclavian vein
- facial --> internal jugular vein

Answer 2

\({\bf{Upper~Limbs:}}\)
> digital veins --> palmar veins --> palmar venuous arches --> cephalic, median antebrachial, basilic (superficial) and radial and ulnar vein (deep) --> brachial vein --> axillary vein
> median cubital vein: connects cephalic + basilic veins; common site of blood removal
> cephalic vein --> axillary vein --> subclavian vein --> brachiocephalic vein (merge w/ jugular veins)

\({\bf{Azygos~Vein:}}\) --> joins superior vena cava
- receives from hemi-azygos vein
- collect from thorax (intercostal veins, esophageal veins, mediastinal veins)
- hemi-azygos vein can ddrain into left brachiocephalic vein or left superior intercostal vein

Answer 3

\({\bf{Inferior~Vena~Cava:}}\) collects fraom organs inferior to diaphragm

\({\bf{Lower~Limbs:}}\)
> plantar veins --> plantar venous arch --> anterior tibial vein, posterior tibial vein, fibular vein
> dorsal venous arch: collects from dorsal capillaries/veins on foot. drained by great + small saphenous veins
> great saphenous vein --> drains into femoral vein
> small saphenous vein --> drains into popliteal vein --> femoral vein
> femoral vein: receives blood from great saphenous vein + deep femoral vein + femoral circumflex --> becomes external iliac vein

\({\bf{Pelvic~Veins:}}\)
> lower limbs, pelvis, lower abdomen drain into external iliac veins --> merge into internal iliac vein --> fusion of external + internal iliac veins make common iliac veins --> left and right fuse to form inferior vena cava
> glutal, internal pudendal, obturator, lateral sacral veins --> form internal iliac vein
> median sacral vein --> empties into left common iliac

\({\bf{Abdominal~Veins:}}\)
> inferior vena cava receives blood from abdominal wall, gonads, liver, kidneys, adrenal glands, diaphragm
- lumbar veins (drain from lumbar region, connected to azygos + hemi-azygos)
- gonadal veins (drain from gonads + empty into inferior vena cava + left renal vein)
- hepatic veins: (drain from liver + empty into inferior vena cava)
- renal veins: (drain from kidneys + empty into inferior vena cava)
- adrenal veins: (drains from adrenal glands + empty into inferior vena cava + left renal vein)
- phrenic veins: (drains from diaphragm + empty into inferior vena cava + left renal vein)
> hepatic portal vein: drains visceral organs

Answer 4

\({\bf{Hepatic~Portal~System:}}\) starts at digestive organs ends at liver. fusion of superior mesenteric + splenic vein. receives from gastric (stomach) + cystic veins (gallbladder)
*liver is the only digestive organ that drains right into the inferior vena cava*

celiac + superior mesenteric + inferior mesenteric arteries ---> flows into hepatic portal system

hepatic portal veins also absorb substances from stomach + intestines like glucose and amino acids

> inferior mesenteric vein: drains from large intestine, left colic + superior rectal veins (drain from descending colon, sigmoid colon, rectum)
> splenic vein: drains from inferior mesenteric vein, spleen, stomach, pancreas
> superior mesenteric vein: stomach, small intestine, large intestine

Answer 5

Adapted from Human Anatomy, Martini, et. al. 9th edition